Children whose mothers smoke during pregnancy have lower levels of high-density lipoprotein (HDL) cholesterol, known to protect against heart disease in later life. By the age of eight, children born to mothers who smoked had HDL levels of about 1.3 millimoles per litre as against a more normal level of 1.5 millimoles per litre among children of non-smoking mothers. This effect was independent of whether children were exposed to cigarette smoke after birth, suggesting prenatal exposure had the most impact on subsequent development, reports the European Heart Journal.
“Our results suggest maternal smoking ‘imprints’ an unhealthy set of characteristics on children while they are developing in the womb, which may well predispose them to later heart attack and stroke,” cardiology professor David Celermajer said. ”This imprinting seems to last for at least eight years and probably a lot longer,” added Celermajer, who led the study at the University of Sydney. Celermajer and colleagues examined the effects of maternal smoking during pregnancy on the thickness of the arterial wall and the levels of lipoproteins in 405 healthy eight-year-olds born between 1997 and 1999. Ultrasound scans were used to measure arterial wall thickness and they took blood from 328 children to measure lipoprotein levels. Researchers believe lower levels of HDL cholesterol at this age could lead to serious impact on health in later life.